Today, a Sichuan Airlines flight with flight number 3U8906 diverted to Guangzhou Baiyun Airport and issued emergency code 7700. In response, Sichuan Airlines officially responded,It is said that flight 3U8906 experienced an aircraft bleed air failure in the air.The crew handled the situation normally according to procedures, and the flight landed safely at Guangzhou Baiyun International Airport at 14:15. The company has arranged to change aircraft for subsequent flights.

Subsequently, the well-known aviation blogger "FATIII" conducted popular science on the air bleed failure of flight 3U8906.

The blogger said that because the air at an altitude of 10,000 meters is thin, modern passenger aircraft use pressurized cabins to ensure oxygen supply.If a malfunction occurs in mid-air and the cabin pressure or oxygen supply cannot be maintained, the crew must descend to less than 3,000 meters as quickly as possible and land as soon as possible.

The aircraft is designed with multiple monitoring systems and redundancies, and each seat and lavatory is equipped with an oxygen mask to provide oxygen during pressure relief.

The civil aviation system also has complete procedures to deal with such situations. China's civil aviation crews receive regular inspections and training to ensure that relevant procedures are proficiently implemented.

"Be sure to pay attention to the safety demonstrations and read the safety instructions when taking a flight. If this happens, there is no need to panic and just follow the instructions of the crew."the blogger said.

In addition, some netizens asked, "Does this also need to be linked to 7700?"

The blogger explained: "In fact, the 7700 is not linked to the severity of the fault, because if special circumstances require priority landing, the 7700 can also be used. If a passenger is suddenly ill and needs to land as soon as possible, the 7700 may also be used."

It is understood that when the aircraft sends out the "7700 code" it means it is encountering an emergency situation, such as mechanical failure or sudden illness of a person on board.

This emergency code is developed by the International Civil Aviation Organization (ICAO) for use in emergencies and is used globally.